The plant’s operator and the utility responsible for the clean-up Tokyo Electric Power Company (TEPCO) detected record radiation levels on a duct which connects reactor buildings and the 120 meter tall ventilation pipe located outside on Friday. TEPCO measured radiation at eight locations around the pipe with the highest estimated at two locations - 25 Sieverts per hour and about 15 Sieverts per hour, the company said.

This is the highest level ever detected outside the reactor buildings, according to local broadcaster NHK. Earlier TEPCO said radiation levels of at least 10 Sieverts per hour were found on the pipe.

FRIDAY, DECEMBER 6, 2013

Let's get back to Fukushima I Nuclear Power Plant, which feels to be working much better than the National Diet in Tokyo if you don't look very carefully.

Remember the exhaust stack between Reactor 1 and Reactor 2, the bottom of which was found in August 2011 to be emitting extremely high radiation? In fact, it was so high that the dosimeter went overscale at 10 SIEVERTS/Hour on the surface of the pipe (see my post from August 2, 2011).

TEPCO finally did the measurement on November 22, 2013 to find out how high.

The conclusion is that it may be as high as 25 sieverts/hour on the surface of the radiation sources, which TEPCO thinks too (see the above gamma camera photo).

The ambient air dose rates near the location were so high that the measurement was done with what looks like a 20-foot pole.

There are reports by the media and blogs that this 25 sieverts/hour radiation was actually measured. It wasn't. TEPCO measured the ambient air dose rates around the two locations where TEPCO thinks the radiation sources exist, andcalculatedthe possible radiation level right at the radiation source.

[.1 sievert per hour, 1 sv in a day will nearly kill you]The highest ambient air dose rate measured was 95 millisieverts/hour, at 1.5 meter from where the STGS (standby gas treatment) pipe is connected to the exhaust stack:

Unit 1 received a scope inspection into the containment structure in previous years that had limited usefulness. Both scopes and robots have been sent into the torus room of unit 1 more recently. These have discovered some areas where there is evidence of damage, high heat and high radiation. Human entries into the reactor building have found obvious damage but nothing that became a piece of major new evidence. Closer camera inspections of the unit 1 refueling floor did find that the concrete reactor cover was partially dislodged. The extent of this may not be fully understood until they clear the debris off of unit 1′s refueling floor. The muon scan of unit 1 that will attempt to image the reactor vessel to determine if any fuel remains within it began in February 2015. This work should be completed in mid-March 2015. A robot inspection inside the containment structure of unit 1 (see above completion) is planned for this spring for unit 1. If successful, this inspection could give significant clues to the extent of the meltdown damage.

Akira Ono, chief of the Fukushima No. 1 plant, said of the second leak that there is another pipe above the suppression chamber and the vent pipe, and it appears that the water is leaking from around that pipe.

But Ono said it is still unknown where exactly the leak is located, and that it is conceivable the water is coming from the containment vessel.

Still, “these are significant findings to help” find the precise locations of the leaks, he said.

The remote-controlled boat was in tainted water inside the torus room that contains the suppression chamber. Radiation levels inside the torus room are running between 0.9 to 1.8 sieverts per hour, dangerously high for human exposure.

Japan lacks decommissioning experts for Fukushima No. 1

International team needed, the sooner the better: experts

Japan is incapable of safely decommissioning the devastated Fukushima No. 1 nuclear plant alone and must stitch together an international team for the massive undertaking, experts say.

At Fukushima No. 1, there is the daunting challenge of taking out cores that suffered meltdown,e cleanup at Fukushima No. 1 will be more difficult than Three Mile Island because the damage is more extensive, involving three reactors instead of one, and more serious because of the greater damage from the bigger explosions.decommissioning of two reactors similar to Fukushima’s began in 2009 at the Hamaoka nuclear plant in Shizuoka Prefecture, but it is in the early stages and is expected to take nearly 30 more years.

According to Tokyo’s Mainichi newspaper, the deaths related to the nuclear disaster at Fukushima that struck following a catastrophic tsunami on March 11, 2011 have topped 1,600. These fatalities include people who died from radiation effects, fell victim of squalid living conditions and committed suicide.

In the latest photo, the shield plug appears intact, but if you look closely the center of the middle piece is depressed downward. TEPCO's analysis is that some heavy debris fell on top of the piece after the explosion, and the shield plug itself (which has three layers) is structurally sound. The shield plug is not likely to be touching the Containment Vessel head, says TEPCO in theaccompanying document.

Diagrams of the shield plug, and TEPCO's analysis on the deformed shield plug, from the accompanying document (Japanese):

(TEPCO's analysis above)

The cause of deformation could be "hydrogen explosion" or "falling of the ceiling crane and other objects". However, as the floor slab (30-centimeter and 60-centimeter thick) surrounding the shield plug is not damaged, it is not likely that the shield plug (made of three layers of ferroconcrete (60 centimeters each) was deformed by the hydrogen explosion. The ceiling crane itself did not make direct contact with the shield plug after it fell, but there was a trolley above the shield plug. So the deformation is likely to have been caused by the fall of the main hoisting hook onto the shield plug.

For building precursor findings of Fukushima Daiichi Nuclear Power Station Unit 3 reactor building top debris removal after

DEBUNKING REACTOR 3 STEAM ALARMISM

(UPDATE 12/31/2013) For those who want the summary of the steam incident since July this year and the Reactor 3 operating floor condition since the March 2011 accident, I have a new post.

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An acquaintance who casually follows the Fukushima I NPP accident sent me a link, quite worried. I opened the link, and I started laughing, then I despaired – realizing that this may be the current level of understanding in the US when it comes to the Fukushima I NPP accident.

I have no idea who this is (“Turner Radio Network – Free Speech, No Matter Who Doesn’t Like It”), but it has an urgent news flash on December 28, 2013:

Persons residing on the west coast of North America should IMMEDIATELY begin preparing for another possible onslaught of dangerous atmospheric radiation from the Fukushima nuclear disaster site in Japan. The Tokyo Electric Power Company (TEPCO) says radioactive steam has suddenly begun emanating from previously exploded nuclear reactor building #3 at the Fukuishima disaster site in Japan. TEPCO says they do not know why this is happening and cannot go into the building to see what’s happening due to damage and lethal radiation levels in that building. Experts say this could be the beginning of a “spent fuel pool criticality (meltdown)” …

The page shows a photograph of Reactor 3 steaming vigorously to lend support to the contention above.

The problem? It is a photo from March 2011 right after the building blew up.

Further down the post,

The video below was taken several months ago by TEPCO. It shows that the roof is totally blown off reactor building # 3

October 10, 2013:

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Overhead crane, and brown cover over spent fuel pool

July 2013 west wall nearly completed

Construction of outer building for Unit 3 between main building and turbine building

Photo: Unit 3 spent fuel pool from above, with a portion of the liner protection system visible at its edges. Source: TEPCO.

Beam Removed from Unit 3 SFP

While clearing debris from around the unit 3 spent fuel pool on Sept. 22, a piece of remotely operated equipment dropped a steel beam into the water. TEPCO workers retrieved it Thursday, according to a release, after practice runs using a mockup of the beam and the SFP. Before the beam was lifted from the pool and set on the ground next to the reactor building, crews also lowered a system of rods and chains into the SFP to protect its liner during the procedure. A water purification system was also installed that TEPCO said doubled visibility in the pool to 5 meters. No damage to the liner or changes in plant conditions were detected after the beam was removed.

March 24, 2011:

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Extensive radioactive steam coming from reactor core. Only the east vertical pillars remain standing, and even they are extenstively bent over. West pillars are completely gone. Only part of the roof framework remains. The picture below wasthe one that I marked up showing the upper left "spider hole" shaft used to lift fuel up from ground floor, sfp at lower left, dryer pool at lower right, center of reactor cover, and crane collapsed (two gray beams) onto the refueling floor.

Reactor No 3

Reactor No3

This is from the south looking north. The roof is at an angle as west wall is gone, but roof (but not crane) is supported on the east side.

Unit 3 looking at the north side, looking south shows that the northwest (closest) corner was destroyed to one level below the top floor. The explosion not only blew out wall panels, but destroyed part of the floor and blew out the structural pillars on the northwest corner.